Select the location where you wish to hang your decoration. Keep in mind that the hook must be placed between two siding pieces' seams.
Lay the siding hook flat on the siding, with the lip pointing up toward the seam. Push the hook up through the seam until it hooks onto the siding's edge.
Tug gently on the hook to make sure it has a firm grasp. Hang the decoration (weighing less than 12 pounds) on the hook.
Determine the hanging location for the decoration. Keep in mind that that the anchor must be installed right below a siding seam so that the decoration hangs from the section of siding closest to the plywood behind it.
Drive 2-inch wood screws through the vinyl siding and into the plywood. Allow the screw head to extend slightly past the vinyl siding to give you something from which to hang the decoration.
Set the decoration in place on the screw head. Adjust the screw's depth if necessary so that the decoration hangs straight down from the screw head, with its back resting lightly against the siding.